[Skiboot] [RFC v2 PATCH 0/6] Faster fast reboot (2x!)

[Nicholas Piggin]

On Thu, 28 Jun 2018 12:54:55 +1000
Stewart Smith <stewart at linux.ibm.com> wrote:

> Currently, on a 128GB p9dsu system (with all that memory on node0), it
> takes around 13 seconds in skiboot to do a fast reboot.
> 
> By doing the clear in parallel, we get this down to ~11seconds.
> By then doing it in parallel with PCI scanning, we're down to ~9
> seconds.
> By then caching BOOTKERNEL rather than re-reading it, we're down to
> ~5seconds.

Very nice result! All the patches and rationales seem reasonable to me.

I can take another look at my patch and write a proper changelog for it
if you want to merge it. Did you have to make any changes?

Thanks,
Nick


> 
> With this patchset, we're down to the following big consumers of time:
> - 2.5s decompressing initramfs in BOOTKERNEL
> - the amazing amount of time it takes for a linux OS to get to the point
>   of issuing 'reboot' to firmware.
> 
> Nicholas Piggin (1):
>   Add cpu_queue_job_on_node() to do node local jobs